Furnace stoker



Oct. 28, 1941. J. A. CASEY FURNACE STOKER- Filed Aug. 30, 1939 Patented Oct.'28, 1941 mm STATES PATENT OFFICE T FURNACESTOKER James A. Casey, Wilkes-Barre, Pa. Application Augn'st 30, 1939, Serial No. 292,725

-' This invention relates to furnace stoker systems and. more particularly to systems suitable Another object is to provide a system of the class described wherein the various parts are driven from a common power source.

A further object is to provide means for automatically breaking clinkers which might form in the ash.

Another object is to, provide the system with adjustably mounted clinker breaking means.

Other objects include the provision of screw and spiral conveyorsfor feeding the fuel and removing the ash; spiral conveyor means for driving .a movable peripheral portion of a fire pot;

and means for using the spiral conveyor driving the peripheral portion of the fire pot simultane-- ously as an ash removing conveyor.

Yet other objects include a fire pot having a rotatable agitating periphery; knob shaped teeth for driving the periphery by a spiral conveyor; inclined ash conveying means; anti-friction means mounted on a peripheral portion of the fire pot; ash receiving means cooperatively associated with a'periphery of the fire pot; safety means to prevent jamming of the ash removal system; and interchangeable means for reversing the positioning of the power drive and ash removal means.

Other objects and advantages of this invention will appear from the following description taken in connection with the accompanying drawing.

In the drawing, wherein like reference characters indicate corresponding parts in the Various figures;

Figure 1 is a plan view partly broken away and showing an apparatus constituting a preferred embodiment ofthis invention.

Figure 2 is a view in side elevation partly in section of the system in Figure 1.

Figure 3 is an enlarged detail view substantially on line 3-3 of Figure 1, illustrating one form of the safety device.

Figure 4 is anenlarged partial cross-section illustrating the anti-friction mounting.

Figure 5 is a cross-section taken along the line 5-5 of Figure 2.

Considerin the drawing system comprises a fire pot extending spiral conveyor N with a horizontally in greater detail, the

2 Claims. (01. 110-45) into the fuel inlet I! in thebottom of the fire pot. This conveyor can be operated under the control of a thermostat or other device for controllably forcing fuel into the fire pot. A shell I3 extending angularly about the fire pot, connects with the housing I encompassing the fuel feed ing conduit I! and serves as a means for introducing the combustion supported air into the fire pot. The air under pressure is supplied from y, the motor driven blower I through the conduit I4, and enters the fire pot through a series of annular air-ports ll formed by the adjacent section of the firepot. A peripheral pdrtion IQ of the fire pot is rotatably mounted thereon and serves as an agitator for preventing the formation of a rigid mass of coke or clinkers, as well as a means for continually agitating the bed of ash forming in the surface of the fire bed to thereby effect a dislodgment of and removal of the ash from the fire bed. 1

The annular periphery I8 is rotatably positioned adjacent the upper edge of the fire pot, and is suitably connectedto a driving means constituting a gear wheel IS. The inter-connection is by means of one or more rods 20, which are bolted as at It and 22 to the drive gear and annulus respectively. This inter-connection may also be accomplished "by welding the parts together.

The gear I9 comprises an inner cylindrical In this manner, the parts may be maintained in a relatively movable state at all times, and in such a way as to preclude the possibilityof ashes jamming or harming the bearing element.

This gear wheel is provided with a plurality of teeth 30, each of which is provided with a knob shaped end SI for engagement with a spiral thread or teeth 32 of the power drive 33. As viewed in Figure 1, with the shaft 88 turnin in a clockwise direction,- the gear wheel I! rotates similarly in a clockwise direction about the .axis

' of the fire pot as a center.

This constitutes a self clearing eonstruction. for freeing the driving connection from the acfor feeding fuel cumulation of ash and clinker. 'The'knob-shaped open topped scoop source for the system. The opposite end of the motor can be connected to a gear box 35 Figure 2 through which the driving power is transmitted to the agitator drive shaft 33 by means of suitable gearing or sprockets 36 and 31. An additional power take-off serves to drive the coal conveyor shafts 38 and 39 respectively. A stub shaft 40 from the gear reducer, has a sprocket 4| connected by a chain with the sprocket wheel 42, which latter serves as the intermediate power source for driving the ash conveyor 54. are so arranged as to provide a limited longitudinal or axial movement, whereby jamming of the parts is avoided. These floating conveyor shafts are assisted by sleeve hearings or couplings at appropriate points throughout the sys- 3 tem, such as at the points 43, 44, 45, 46,'etc.

The end of each conveyor may preferably be hard-surfaced to give great wear resistance. The hard-surfacing material or treatment of the metal parts to effect a case-hardening is preferably at the ends 41, 48, 49, etc., of the various spiral conveyor elements.

The ash conveyor 54 rotates in an inclined tubular housing 58, the top half of which is omitted in that portion which is in the path of falling 'ash from the burner or of accumulated ash beneath the burner, so that the lower end portion of the housing 56 has the form of an 66'. A fitting 91 is clamped about the housing 66 adjacent the upper end of the scoop 65' by set screw 81', having a plate 5| positioned in a plane'perpendicular to the plane of rotation of the gear wheel i8. The scoop 68' and the plate 5| together constitute a breaker box 50 in cooperation with the end portion 41 of the screw 32.

It will be understood that ashes may accumulate and fill the ash pit, except that part in the vicinity of the breaker box, even up to the level of the top of the burner, the gear wheel I9 and the connecting rod 20, by their continual rotation, maintaining a free path of travel through the mass of ashes.

The presence of this bounding mass of ash causes clinkers broken by the rotation of the annular agitator element 83 at any point in the periphery of the burner, to be carried around until they come to the region where the ash mass is depleted by the action of the ash con-. veyor. The clinkers at this point fall into the breaker box and are carried away by the ash conveyor. If they happen to be so large as to lie on top of the exposed part of the conveyor screw, against the plate ll, they are crushed against said plate by the connecting rod 20 or the knobbed periphery of the gear wheel I! and the end portion 41 of the screw 32, the fragments I dropping between the helices of the conveyor.

The drive screw 32 and the gear wheel I9 are positioned above and closely adjacent the scoop 65' at one side, and rotate in such direction as to deposit such clinkers as may fall upon it, into said scoop.

The various conveyor shafts and bearings ing shaft 51, This latter is provided with a forked outlet having conduits 58 and 59 arranged to feed respectively into ash receptacles i0 and GI. Flexible connections 62 and 63 are arranged to connect these conduits with the ash receptacles and to provide a means whereby the receptacles when filled may be replaced.

The ash outlet pipe 51 is provided with a gravitationally closed safety door 64. If the ash containers 60 and SI should get filled before an attendant, or other designated person, can remove one of them and replace it by an unfilled container, the pressure of the ash packing in the system will force the safety door 64 open and allow the excess ash to drop to the floor of the furnace room. In this latter respect, it will be noted that the end 55 of the conveyor 54 is shaped to provide an enlarged paddle or pressure shape meansserving to cooperate with the safety door and eifecting the opening of the latter.

It will be noted that the ash pipe connections 65 are so arranged that the ash distributing pipe 51 may be connected to either side of the ash conveyor housing 56.

Although a preferred embodiment of this invention is illustrated and described, variations .within the true spirit and scope of the same will be determined by the appended claims.

What I claim is:

1. A furnace stoker comprising a .fire pot, means for forcing fuel into said fire pot, said fire pot including a rotatable rim at the top, a gear wheel with knob-shaped teeth below said rim and connected therewith for rotating said rim to break off clinkers from the ash mass on top of the fire pot, an ash conveyor underlying a part of said rim, the end of said conveyor being in a breaker box in ash receptive relation to the edge of said part of said rim, said breaker box including a plate above the end of said conveyor, in close relation to the path of travel of said rim rotating means, said plate and said rim rotating means coacting to crush clinkers falling between them, and to permit the gravitation drop of the fragments into said conveyor, and a driven spiral conveyor positioned above and in lateral proximity to said breaker box, the helices of which mesh with said teeth for rotating said gear wheel, and which helices rotate in a direction to convey ashes from said teeth and drop them into said breaker box.

2. A furnace stoker comprising a fire pot, means for forcing fuel into said fire pot, an ash coilveyor underlying a part of the rim of the fire pot, the end of said conveyor being in a breaker box positioned in ash receptive relation to said rim, said breaker box including a breaker plate, a ring rotatably mounted surrounding the fire pot having radially extending teeth arranged to pass over the breaker box, a spiral conveyor positioned above and in lateral proximity to the breaker box, the helices of which mesh with the teeth of said ring to rotate the same and which helices rotate in a direction to convey ashes from said teeth into the breaker box.

JAMES A. CASEY. 

